The purpose of this project is the attempted isolation of a novel infectious agent from patients with the acquired immune deficiency syndrome (AIDS). Two approaches are being taken. The first approach is the inoculation of mink with pooled samples from either terminal AIDS patients or patients with the apparent prodromal phase of AIDS. The rationale is that AIDS patients have a variety of findings similar to ones observed in Aleutian disease of mink, a disorder of immune function caused by a nondefective parvovirus. Some of these findings include plasmacytosis, immune complex disease, glomerulonephritis and hypergammaglobulinemia. The plan is to observe inoculated mink over an extended period of time for development of an AIDS-like syndrome and possibly to assay for evidence of infection with putative AIDS agents such as HTLV III. The second aspect of the study is to inoculate goats and mice with brain material from AIDS patients that have died with the encephalopathy observed in these patients. The purpose for this portion of the work is to determine if a spongiform-like agent (such as scrapie or Creutzfeldt-Jakob) has a role in AIDS.